FARKLI ORTAM KOŞULLARINA MARUZ BIRAKILAN KOMPOZİT MALZEMENİN EĞİLME DAVRANIŞLARININ DENEYSEL VE TEORİK OLARAK İNCELENMESİ

Yıl 2016, Cilt: 1 Sayı: 21, 27 - 37, 31.07.2016

Ayla Tekin , Ümran Esendemir , Ayşe Öndürücü

Öz

Kompozit malzemeler uygulama alanı olarak farklı iklim koşullarında kullanıldıklarından çok büyük sıcaklık değişimlerine ve farklı ortam şartlarına maruz kalabilmektedir. Bu çalışmada, dört farklı ortam koşulunda bekletilen örgü cam elyaf takviyeli epoksi kompozitin eğilme davranışı incelenmiştir. Standartlara uygun olarak hazırlanan numuneler kullanılarak yapılan deneylerle farklı ortamlarda bekletilen malzemelere ait elastisite modülleri tespit edilmiştir. Dört farklı ortamda bekletilen numunelerin üç nokta eğme deneyi sonucu elde edilen sehim değerleri ve eğilme dayanımları karşılaştırılmıştır. Deneysel olarak elde edilen sehim değerlerinin teorik olarak hesaplanan sehim değerleri ile birbirine çok yakın çıktığı görülmüştür. Sonuç olarak; saf suda, deniz suyunda ve asitli suda bekletilen kompozit numunelerin yük taşıma kapasitesinin, oda sıcaklığı ortamında bekletilen numunelere göre daha düşük olduğu görülmüştür.

Anahtar Kelimeler

Kompozit malzeme, sehim, ortam şartları

EXPERIMENTAL AND THEORETICAL ANALYSIS BENDING BEHAVIORS OF COMPOSITE MATERIALS SUBJECTED TO DIFFERENT ENVIRONMENTAL CONDITIONS

Öz

Composite materials can be exposed to very large temperature changes and different environmental conditions as they are used in different application areas and climates. In this study, bending behavior of epoxy composite material reinforced with meshed fiberglass held in four different environmental conditions was examined. Modules of elasticity of the materials held in different environments were determined with tests performed on samples prepared according to standards. Deflection values and bending strength obtained as a result of three-points bending tests held in four different environmental conditions, were compared. Deflection values from test results seems analogous with theoretically calculated deflection values. As a result of this experimental and numerical study, load carrying capacity of the composite samples held in pure water, sea water and acidic water was observed as lower than the ones that were held in room temperature conditions.

Anahtar Kelimeler

Composite material, deflection, environmental conditions

Kaynakça

• Sudhir S. Mathapati, Shivukumar S. Mathapati, 2015. Testing and analysis of mechanical properties of E-glass fiber reinforced epoxy polymer composites. International Journal of Research and Innovations in Science&Technology, 2(1), 46-52.
• Rathnakar, G., Shivanan, H.K., 2013. Experimental evaluation of strength and stiffness of fibre reinforced composites under flexural loading. International Journal of Engineering and Innovative Technology (IJEIT), 2 (7), 219-222.
• Almusallam, T., Al-Salloum, Y. , Alsayed, S. , Alhozaimy. A., 2002. Durability of GFRP rebars in stressed concrete beams at different environments. 6th Saudi Eng Conf, KFUPM, Dhahran, 3,263-276.
• Manalo, A.C., Aravinthan, T., Karunasena ,W., 2010. Flexural behaviour of glue-laminated fibre composite sandwich beams. Composite Structures, 92, 2703-2711.
• Belevi, M., İnançer, G., 2008. Darbe ve ortam şartlarının kompozit malzemelerin mekanik özelliklerine etkileri. Makine Teknolojileri Elektronik Dergisi, 4,19-31.
• Ghafoori, E., Motavalli, M., 2013. Flexural and interfacial behavior of metallic beams strengthened by prestressed bonded plates, Composite Structures. 101, 22–34.
• Kılıç, O., Aktaş, A., Dirikolu, M.H., 2001. An investigating of the effects of shear on the deflection of an orthotropic cantilever beam by use of anisotropic elasticity theory. Composites Science and Technology, 61, 2055-2061.
• Esendemir, Ü., 2005. The effects of shear on the deflection of linearly loaded composite cantilever beam. Journal of Reinforced Plastics and Composites, 24(11), 1159-1168.
• Esendemir, Ü., Usal, M.R., Usal, M., 2006. The effects of shear on the deflection of simply supported composite beam loaded linearly. Journal of Reinforced Plastics and Composites, 25(8), 835-846.
• Usal, M.R., Esendemir, Ü., Usal, M., 2008. Static and dynamic analysis of simply supported beams. Journal of Reinforced Plastics and Composites, 27(3), 263-276.
• Tagarielli, V.L., Fleck, N.A, Deshpande, V.S., 2004. Collapse of clamped and simply supported composite sandwich beams in three-point bending. Composites: Part B, 35, 523–534.
• Esendemir, Ü., Durak, E., Tunay, R.F. Usal, M.R., 2015. Flexure behavior of composite cantilevers subjected to different environmental conditions. Materials Testing, 57, 227-233.
• Lekhnitskii, S.G., 1981. Theory of Elasticity of an Anisotropic Body. Mir Publishers, Moscow.
• Jones, R.M., 1975. Mechanics of Composite Materials, Mcgraw-Hill, Kogakusha, Tokyo.
• Esendemir, Ü., 2004. An elastic-plastic stress analysis in a polymer-matrix composite beam of arbitrary orientation supported from two ends acted upon with a force at the mid point. Journal of Reinforced Plastics and Composites, 23(6), 613-623.
• Esendemir, Ü., 2009. Derivation of equations for flexure and shear deflections of simply supported beams. Pamukkale University Journal of Engineering Sciences, 15(2), 187-193.
• Mourad, A.H.I., Abdel-Magid, B.M. El-Maaddawy, T. Grami M.E., 2010. Effect of seawater and warm environment on glass/epoxy and glass/polyurethane composites. Applied Composite Materials, 17,557-573.